Sanford, who had a goal and two assists, was recalled from San Antonio of the American Hockey League on Oct. 16.
"I didn't know exactly how it would go," Sanford said. "I came in and tried to play with confidence. I got a great opportunity and I think I've done a good job of taking advantage of it for now. My linemates (Ryan O'Reilly, David Perron) have been a great help, the whole team as well. Hopefully, I can keep playing this way."
WATCH: [All Blackhawks vs. Blues highlights]
Patrick Kane had two goals and an assist, Artem Anisimov had a goal and two assists, and Corey Crawford made 30 saves for Chicago (6-3-2), which had won three of its past four.
"I think they just outplayed us," Kane said. "Obviously, when you're getting outplayed, you're going to take some more penalties. That's kind of something that's been troubling us the first start of the season. We seem to be in the box a little bit too much, it kind of halts our game and our momentum. It's something to work on."